The Rise of Browser-Native Ransomware: A New Era of Cyber Threats
From high-profile incidents like WannaCry to the recent MGM Resorts breach, ransomware has evolved into one of the most destructive cyber threats targeting businesses. While companies reportedly pay nearly $1 billion annually in ransom, the true cost often comes from operational downtime, reputational damage, and long-term security implications.
Traditionally, ransomware attacks compromised devices by tricking users into downloading malicious files that would encrypt or delete critical data. However, with the shift to cloud and SaaS platforms, endpoint devices are no longer the primary target—the browser is now the gateway to enterprise resources.
SquareX Sounds the Alarm on Browser-Native Ransomware
Security researchers at SquareX have uncovered a disturbing trend: ransomware that operates entirely within the browser. Building on their previous discoveries of vulnerabilities like Polymorphic Extensions and Browser Syncjacking, SquareX is now warning that attackers are actively developing browser-native ransomware, a new form of cyber extortion that requires no file downloads and bypasses traditional endpoint defenses.
Vivek Ramachandran, founder of SquareX, explains,
“We’re witnessing a rise in browser-based identity attacks, such as the recent Chrome Store OAuth breach. The necessary ingredients for browser-native ransomware are already being used by adversaries—it’s only a matter of time before attackers fully weaponize them. Since these attacks don’t involve file downloads, traditional EDRs and antivirus solutions are powerless against them. The industry must prioritize browser-native security to combat this next-generation threat.”
How Browser-Native Ransomware Works
Unlike conventional ransomware, which encrypts files on a local device, browser-native ransomware hijacks a user’s digital identity—exploiting the widespread use of cloud storage and SaaS applications. SquareX has demonstrated multiple real-world attack scenarios leveraging AI-powered automation to streamline the process with minimal attacker involvement.
One such attack involves:
- Social engineering a victim into granting permissions to a fraudulent productivity tool.
- The attacker then maps out all the SaaS applications linked to the victim’s email.
- Using AI agents, passwords for these applications are systematically reset, locking the user out of their accounts.
- The attacker demands ransom to restore access, holding enterprise data hostage.
Another method targets cloud storage services like Google Drive, OneDrive, and Dropbox, where attackers:
- Use stolen credentials to copy and delete all files stored under the victim’s account.
- Gain unauthorized access to shared drives containing sensitive company data.
- Extend the attack to colleagues, customers, and partners, rapidly escalating the impact beyond a single individual.
Why This Threat Is Different – And More Dangerous
Traditional ransomware is confined to a single endpoint, but browser-native ransomware is a network-wide threat. A single compromised user can expose an entire organization’s cloud-based assets, making containment significantly harder.
With fewer files being downloaded and most business operations moving to the cloud, attackers are following the data—and enterprises must adapt. Just as EDRs became essential for detecting file-based ransomware, a browser-native security solution is now critical for combating these emerging threats.
What Comes Next?
SquareX continues to lead research into browser security threats through its Year of Browser Bugs initiative, exposing fundamental weaknesses in modern web security. Past discoveries include Browser Syncjacking and Polymorphic Extensions, with more critical findings to come.
To learn more about SquareX’s security research, visit: https://sqrx.com/browser-native-ransomware
About SquareX
SquareX provides the industry’s first Browser Detection and Response (BDR) solution, enabling real-time protection against browser-based cyber threats, including identity theft, malicious extensions, AI-powered phishing, and browser-native ransomware.
For security inquiries, contact: founder@sqrx.com
For press inquiries, email: junice@sqrx.com
